1. Field of the Invention
The present disclosure relates to semiconductor technology, and in particular relates to a light-emitting diode (LED) chip that can effectively improve the brightness.
2. Description of the Related Art
Due to advantages such as small size, fast switching speed, low power consumption and good durability, light-emitting diodes (LED) have been involved in various applications, such as lighting, car indicators and traffic signals. A light-emitting diode usually includes a p-n junction constituted of, for example, a p-type semiconductor layer and an n-type semiconductor layer. By an appropriate bias applied to the p-n junction through the electrodes respectively connected to the p-type semiconductor layer and the n-type semiconductor layer, the electrons combine with the holes at the p-n junction. As a result, energy is released and therefore a luminescence phenomenon happens.
In a conventional light-emitting diode manufacturing process, a current-spreading layer is formed on the p-type semiconductor layer such that the current can be uniformly transferred to the p-type semiconductor layer and the p-n junction (i.e., the active layer) connected thereto. In order to further improve the light extraction efficiency (LEE) of the light-emitting diode, it is known that an opening pattern that penetrates through the current-spreading layer may be formed to increase the light emission angle of the light generated by the active layer.
However, since the opening pattern may also result in an obstruction to the current-spreading in the current-spreading layer, the brightness uniformity and the electrical properties (for example, the driving voltage) of such a light-emitting diode needs to be improved. Accordingly, a light-emitting diode chip that can improve the luminous efficiency of light-emitting diodes while maintaining the driving voltage of the light-emitting diodes within a suitable range is still under requirement.